refactor: move studio to frontends workspace

- Move studio from root to frontends/studio/
- Add owner-tools frontend for live blog admin UI
- Add shared ui component library
- Set up npm workspaces for frontends
- Add enhanced code block extension for editor

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontends/owner-tools/src/stores/app.ts

@@ -0,0 +1,64 @@
+import { atom, map, onMount } from 'nanostores'
+import { getSettings, getSettingsSchema, saveSettings as apiSaveSettings } from '../api'
+import type { Settings, SettingDefinition } from '../api'
+
+export const $panelOpen = atom(false)
+export const $regenerating = atom(false)
+export const $error = atom<string | null>(null)
+export const $settings = map<Settings>({})
+export const $schema = atom<SettingDefinition[]>([])
+export const $dirty = atom(false)
+
+export function openPanel() {
+  $panelOpen.set(true)
+}
+
+export function closePanel() {
+  $panelOpen.set(false)
+}
+
+export function updateSetting(key: string, value: string) {
+  $settings.setKey(key, value)
+  $dirty.set(true)
+}
+
+async function softReload() {
+  const res = await fetch(window.location.href)
+  if (!res.ok) throw new Error('Failed to fetch page')
+
+  const html = await res.text()
+  const parser = new DOMParser()
+  const newDoc = parser.parseFromString(html, 'text/html')
+
+  const currentPage = document.getElementById('page')
+  const newPage = newDoc.getElementById('page')
+
+  if (currentPage && newPage) {
+    currentPage.outerHTML = newPage.outerHTML
+  }
+}
+
+export async function saveSettings() {
+  $regenerating.set(true)
+  $error.set(null)
+
+  try {
+    await apiSaveSettings($settings.get())
+    await softReload()
+    $regenerating.set(false)
+    $dirty.set(false)
+  } catch {
+    $regenerating.set(false)
+    $error.set('Failed to save')
+  }
+}
+
+onMount($settings, () => {
+  getSettings()
+    .then(data => $settings.set(data))
+    .catch(() => $error.set('Failed to load settings'))
+
+  getSettingsSchema()
+    .then(data => $schema.set(data))
+    .catch(() => {})
+})